PURPOSE: To provide a damper for the rocking of a vehicle capable of controlling a damping force to a wheel stroke accompanied by the relative displacement like roll, pitch, etc., between two left one right wheels and a wheel stroke like bounce not accompanied by the relative displacement between two wheels.

CONSTITUTION: Variable throttle valves 9A, 9B, 10 are interposed respectively in cross pipe lines 7A, 7B interconnecting one upper chamber U and the other lower chamber L of hydraulic cylinders 4L, 4R interposed between a car body 3 and two left and right wheels 1L, 1R and a communicating pipe line 8 interconnecting the upper chambers U or lower chambers L themselves of both hydraulic cylinders 4L, 4R. The damping coefficient of the variable throttle valve 10 in the communicating pipe line 8 is controlled by a damping force control means 11 in the roll and pitch to control the damping force for the roll of the car body along with the roll of the relative displacement of wheel strokes between both wheels so that the damping coefficient of the variable throttle valves 9A, 9B in the cross pipe line 7A, 7B are controlled in bounce at the same time to control the damping force for the roll of the car body not accompanied by the relative displacement.